Process of bucking vegetable material.



compound which is soluble and easily re- K llian.

- rarer 'rcfi RENE BGHN, OF MANNHEIM, GERMANY, ASSIGNOR TO BAIDISCHE AIIILIN dz, SQDAi FABRIK, OE LUDWIGSHAFEHrOIfiTHE BHINE, GEE-MANY, CQRPORATIQN.

rnoonss or BUCKING vnGamBLn-raarnnrrin Specification of letters Patent.

' Patented cat. is, 1915.

rmnr wm Qrig'inal application filed January 27. 1909, Serial no. iv-4,485. mandate this applicationfiled November 6, 1913. Serial No. 799,434.

To all wizomit' may concern:

Be it known that lg'REnr': BOHN, Ph. 1)., citizen of the .Swiss Republic, residing at Mannheim, Germany, have invented new and useful Improvements in the Process of Bucking Vegetable Material, of which the following is a specification.

This application is a division of my original application Serial No. 474,485, filed January 27, 1909, and relates to'a process. or" bucking. v

Few, if any, coloring matters, when dyedor printed on vegetable fiber, are perfectly. fast against bucking (that'is, heating for a considerable time with dilute caustic alkali solution), particularly when the'bucking is carried out under pressure. Attemptsliave been made to avoid this disadvantage of bucking by adding an inorganic oxidizing agent, such for instance as sodium bichrof mate and'potassium permanganate, to the bath used. These, however, are not satisfactory because, when bichromate is used, the chroiniuni oxid which is formed colors the material yellow, and'also when permanganate is used, the material is stained and the removal or" such stains is acomplicated process and tends to weaken the fiber.

l: have now discovered that vegetable material dyed or printed with vat coloring matter can be successfully bucked without the color passing into the White or spreading beyond its proper limits, if 'the bucking vat contain dilute alkali solution and an organic ducible in the presence of alkali. The alkal used may be caustic or carbonate or a salt possessingan alkaline reaction, like sodium phosphate or borax, or. again mixtures of these alkalis can be used. As examples of suitable soluble and easily re ducible organic compounds I mention anthraquin'one derivatives ;and nitrog" derivativ'es, and in particular salts of anthraqumone sulfonic acid, anthraquinone-disulfonic acid,tnitrobenzenesulfonic acid, and nitro-tolueuesulfonic acid.

In order to prepare a bucking vat I take, for instance,- the. following ingredients in approximately the proportions indicated,

namely 4,000 parts of water, 13 parts of solid caustic soda and 8 parts of the sodium salt of nitrobenzene sulfonic acid, or instead of 8 parts of the sodium salt of nitrobenzene sulfonic acid the same quantity of the sodium salt ofanthraquinone monosulfonic acid or anthraquin one 'disulfonic acid can be used. The material to be bucked is introduced into this bath and boiled for about 2 hours at a pressure of 2 atmospheres in excess of ordinaryfpressure.

1. The process of bucking vegetable material dyed or printed with vat coloring matter, by heating the said material with a dilute alkali solution inthe presenceof an easily reducible inthe presence of alkali.

.2. The process of bucking vegetable material dyed or printed with vat coloring matter, by heatingthe said material with a dilute caustic soda solution in the'presence of a salt of nitrobensene-sulfonic acid.

3. The" process oilbucking vegetable ma- .terial dyed'oi printed with vatcoloring mat. ten-by heatingtii'e said material with a (11 lute caustic soda solution" in the presence'of fonic acid. v r

In testimony whereof I have hereunto set my hand in the presence of two subscrib ng 

